Airborne bodies and in particular self propelled missiles



March 31, 1959 H. P, G. A. R. VON ZBOROWSKI AIRBORNE BODIES, AND INPARTICULAR SELF PROPELLED MISSILES Filed J l 22, 1952 4 '2 Sheets-Sheet1 Q N g March 31, 1959 H. G. A. RI VON ZBOROWSKI 2,879,955

AIRBORNE BODIES, AND IN PARTICULAR SELF PROPELLED MISSILES Filed July22, 1952 2 Sheets-Sheet 2 ATTORNEY United States Patent p 2,879,955PatentedMar. 31, 1959 AIRBORNE BODIES AND IN PARTICULAR SELF PROPELLEDMISSILES The present invention relates generally to airborne bodies(this expression including all bodies travelling through air and havingan aerodynamic lift) which carry a charge of matter (for instance apropellent, a fuel, etc.) which is being consumed as'said body istravelling. My invention is more particularly concerned withrocket-propelled devices, and especiallywith missiles carrying adestructive explosive charge.

TThe object of my invention is to provide a body of this kind which isbetter adapted to meet the requirements of practice than those known atthe present time.

.According to my invention, such a body includes, in combination withaerodynamic control means for giving said body a positive incidence orupwardly inclined attitude with respect to its path of travel, so thatan aerodynamic lift is constantly maintained which opposes the action ofgravity on said body, means (which may be constituted by the abovementioned charge of matter itself, suitably arranged for this purpose)for automatically varying this lift in accordance with the consumptionof said matter so as to compensate, either fully or partly and inaccordance with a predetermined law, for the variation-of weight of thisbody resulting from the consumption of its charge of matter.

Other features of my invention will become apparent intthe courseof thefollowing description thereof with reference to the accompanyingdrawings, given merely by way of example, and in which:

Fig. 1 shows an anti-tank missile according to my invention, the toppart being in axial section and the lower part-in elevation, withportions cut away;

Fig. 2 is a cross section on the line 11-11 of Fig. 1;

Fig. 3 is an enlarged section on the line III-III of Fig. 1;'

Fig. 4 is a sectional view on an enlarged scale of a detail of Fig. 1;

Fig. 5. is a diagrammatical view illustrating a modification of the samedetail;

Figs. 6m 8 are diagrammatical views showing different arrangementsof a'spoiler included in the device shown by'the above mentioned figures;

Fig. 9 shows a modification of the armored head of the missile.

,"The following description relates toan anti-tank projectile. Thisprojectile includes the following elements:

(a) A war head including a hollow charge 1, a hollow. armoredpoint 2located ahead of said hollow charge and capable of opening a passage forsaid hollow charge in any Eprotective structure located in front of thetank armor wall proper, andcharge igniting means 3 such for instance asa delayed action detonator capable of starting, the explosion of thehollow charge 1 after the armor point 2 has already opened a passagethrough the proteetive structureof the tank;

(b) A main propelling system 4, advantageously of thei'powder'rockettype;

(c) A starting or launching propelling system 5 fixed on the projectileand which is also preferably of the powder rocket type; and

(d) Means for enabling the projectile to have, and keep, along its pathof travel, a lift such that at least a portion of its trajectory isnearly rectilinear.

Preferably," the main propelling system i disposed line with and aheadof the starting propelling system and I provide, for the jet ofcombustion gases issuing from the main propelling system, an annularnozzle or outlet 6 (or a plurality of outlet orifices disposedannularly).

Furthermore, according to my invention, account being taken of the factthat the weight of the engine and the position of its center of gravityvary as a consequence of the consumption of powder, means are providedfor causing the ratio of the total weight of the projectile to theaerodynamic lift thereof (controlled through means which will behereinafter described) to comply with a predetermined law fixed inaccordance with the desired path of travel of the projectile.

If the path of travel is to be substantially rectilinear (which isdesirable in order to increase the probability of striking a giventarget), this weight to lift ratio should remain substantially equal to1.

For this purpose, the propelling system 4 may be arranged so that thevariation of its thrust and/or the displacement of the center of gravityof the projectile resulting from the consumption of the powder used forthis propelling system comply with the above mentioned law. Concerningthe thrust factor, the propelling system should be arranged in suchmanner that this thrust dej creases as more and more powder has beenconsumed so that, for a constant incidence or attitude of flight, the

lift decreases simultaneously with the total weight and at the samerate, whereby'the ratio of weight to lift reand which assists inproducing the angle of inclination, decreases as the total weightdecreases.

I Thus, the incidence, and therefore the lift of the projectile willdecrease as the total weight decreases as a consequence of theconsumption of powder. It will be possible, by a suitable choice of thelaw determining the relative dis-[ 7 placement (due to the consumptionof powder) of the center of gravity with respect to the center of lift,to

obtain such conditions that the weight to lift ratio' remainssubstantially constant as the projectile is travelling.

In both cases, it-will be advantageous to give the powder bars whichconstitute the reserve of propulsive energy surface of each bar that isburning, it will be readily un-- derstood that non cylindrical bars ofrevolution give a lawof variation of the thrust which depends upon theshape of their generatrices.

As for the displacement of the center of gravity, it is determined byalaw which depends upon the shape the device that the center of gravityof the main propelling system is located, after combustion of the powderof the starting or launching propelling system, at the rear of l thecenter of gravity of the whole projectile, combustion of the powder ofthe main propelling system then producing a frontward displacement ofsaid total center of gravity and therefore a decrease of the angle ofincidence.

It should be noted that it will be advantageous to arrange the mainpropelling system 4-so that it keeps the speed substantially constantduring the duration of the flight (balancing of the drag), a speed ofabout 500 3 metresI-per se'con'd. beingtconsidered as favorable forthis" kind. of projectile, because it, makesgitpossible. to..use.;a1launching propelling system of relatively small weight, to obtain asufficient perforating power of the armored pointl2 and to reducethe-duration. oftfiight to values:

compatible with the destruction of moving targets:..(fromr 2 to.- 3seconds foritargets located iat-IOOO-ISOO-metres).

Concerning; the launching propellingrsystem. 5, it. is? arranged, asalreadyindicated, in. such manner that its".

envelope is incorporated in the'projectilebody, to avoid thedangerswhich ,would be-runrby troopsdocated: ahead" of the. launching station,if. this launching: system. were" detached after it hasplayed its part.

On: the other hand, it-isadvantageous to distribute: the powder bars.of. the launchingypropelling system: in

atleast.two-groups,,disposed in tandemdike fashion;with:, respect-toeach other, the bars 5b of the rear. group gbeings.

fewer in number and at a greater distance from. each other? than thebars Saof the frontgroup This propelling systemrfurther includesa'frangible rear;

diaphragm 7 of .a resistancesuchthatit is destroyed only. when: theinternal pressure of the-system, afterignitingz thereof (preferablyelectrical. igniting), has reached at:

predetermined value; for instance; ahout lol) kgs; per square:centimeter the" combustion gases then. escaping throughnozzle 8..

Advantageously, the envelope of the: auxiliary propellingsystem isgivena slightly convergentshape-toward the front, which facilitatesthearrangement of the outlet. nozzle 6- of. the mainpropellingsystem"(without increas ing the maximum diameter ofthe'projectile). andis further favorable for aerodynamic stability.

Such an auxiliary propellingr system" achieves a:: high stability ofcombustion; andkan', improved'fsafety concerns; in the critical internalpressuremottobeexceeded;

To givethe projectile apositive or upwardly inclined incidenceon. itstrajectory and .to maintain. this. incidence,. the projectileisfittedwith aniaerodynamic controlzsystern';

subjected to the action of a weighted or pendular device;-

so. that the incidence remains constantlyx positive-and. of the-samevalue regardless of1th'epositionwof the-projectile when it turns aboutits .longitudinalaxis.

Such a control. system is for. instance-constituted, asv shown by Figs.1 and 3, by aring19 freely rotatable in the" intervalbetween thehollowcharge 1 and the main pro-' pellingzsystem (advantageouslywiththeinterposition of. a ball bearing .a. counterweight 11. and a spoilerullprojecting slightly from the outline of the projectile cross section,these two elements being? located on. the same side of ring 9, so thatsaidspoiler always projects from,v

the lower portion of the projectile andcreates in this. region a zone ofaerodynamic overpressure capable ofproducing the desired positiveincidence.v Although; the

pressure of the air on the spoiler will have some tendency, to. exert adownward torque onthenose: of the-missile, the dimension-of: the spoileris-such that; this ;torque is much. less than the upward aerodynamicpressure. createdizin front of the spoiler, so. that the resultantthrust on the nose-of the missile is upward;

A. tail unit, preferablyconstituted byarrear annular wing ofa diameterequal to the caliber of the projectile,

is advantageously provided for stabilizing. said projectile on itstrajectory.

But if this tail unit is. adapted to. work satisfactorily at. thesupersonic speedlfor which-the: projectileis de-- signed, it mighthappen that, during the launching period (wherethe speed is subsonic andthe stabilizing effect of 'the tail unit is relatively small), the axis;of the projectile should assume the wrong direction.- In particular,.wh'en..the projectile is passing fromr csubsonic to supersonic speed, itcould.be stabilized only by means-of a tail unit. of a diameter greater.thtmsthat of. ,said 1 projectile;

In order to obviate this diificulty,;- I..make"use' of' an' arrangementillustratedby Figs. 1. andA.

I provide, at the outlet. ofthe-nozzleS ofthe-launching;

propelling system, adjustable deflectors; for instance a: plurality of.spoilers. 14 (four in. thetexamplel illustrated).. distributed at equalangular intervals along the periphery of the nozzle and capable, whenthey are made to project into the gas jet (as shown for the lowerspoiler in Fig. 4), of deflecting said jet and therefore of modifyingthe direction of the propulsive thrust:

These spoilers are operated by a system, for instance including dynamic;air intakes; sensitive to angular dis'-- placements of the'axisof'theprojectile" so as to exert a correcting effect tending to return the"projectile axisinto its initial direction.

Preferably,I couple diametrically'opposed spoilers with each otherthrough adevice having, some. flexibility, so that the operation of onecauses the other to be brought into retracted position: For thispurpose, for instance, every spoiler 14 is mounted at one end of a lever15 pivoted in its middle part about an axis 16, the other end of this"lever being-coupled'with the corresponding 'end of thediametrallyopposed lever through aring element 17, which is 'madeflexible in order to=avoid" 'play."

It is therefore necessary, intheexample shown by tlie drawing,to'provide'two flexible rings-'17, disposed one behind the'other.However, the points-where the respective'levers 15are in contactwiththese rings.must all 'be'- located in the same plane at rightangles-to the axis 'o'fltheprojectile; For this purpose, every lever.l's bears'against' asmall projection 17a of'theedgeof'thecorrespondingt. ring 17, this projection extending t'owardtherearfon that front ring 17 and toward the-front= for the rearrmg l'l,whereby the centers of th'ese four projectionsare locatedn in the sametransverse plane. L

The dynamic air intake control means -may'be constrr tuted,'. as shownby the drawing; by four" manometrie': boxes 18 the inner wallsof whichare flexible and bears: respectively against the forwardends of levers15 (which-f forward" ends in turn. bear against elastic-rings 17) and.

theouter wallsof which, constituted'by the i envelope of the projectile,are provided with respective air intakes 19.-

Ifit is desired to collect a portion nof the dynamic:-

pressure when the projectile gets slightly inclined on its;

trajectory, it is advantageous to give a sharp bevelled? shape to therear edge of 'each orifice 19', as shown by Fig. 4. This rearedge mightbe made tol project from'ta the wall of the projectile to increas'e theair inflow."

On the contrary, if it is desired merely tozutilize the variations of.static pressure taking! place on Ithe rear part,

of smaller diameter, ofthe projectilebody,v when 'saidi projectileassumes an undue.oblique positionzonvits trajec-t tory, I may, asshownbyFig. 5, provideholeslQ having straight edgesand: locate' thepoint where the flexible walls of boxes 18 act upon levers 15a betweenthecfub' crums 16a of these levers andthe correspondingcspoilers.

Preferably, in order to take into account theifactthati thecounterweight 1 1. of? thearotary." control member (spoiler 12) tends tobring the center.ofygravitys.of!tha projectileawaytrbmthe: axis of.symmetry-thereof, means will be provided for slightly-deflecting, the?thrust \so-thati. it passes exactly through this center. ofgravityeSUCI'M meansmay be constituted, asshownby the drawings,.by applying asmall gravity load on the levers 15 whichcon'; trol spoilers 14, thisload being, constituted, for instance, by; the weight of" rings 17 'inthe construction t of Fig.4;

and" by a special counterweight'20 in the'constructionof ner as toreduce the importance of this transvers'eb component. I

For this purpose, in the constructionof.Figao -thea spbilers 'are'inclined toward the front with respeet to the jet and iii-this case theresidual transverse component facilitates the displacements of thespoiler toward its active position under the action of its manometricbox.

In the construction of Fig. 7, the spoilers are inclined toward therear, in which case it is the displacement toward retracted positionwhich is facilitated.

In the construction of Fig. 8, the spoilers have a curved shape(determined by experiments and calculation) such that thetransverse-component is reduced or eliminated.

A'projectile such as above described may have its main elements made ofa light metal or alloy so that it can be easily carried by an infantryman. It can be launched by means of a very simple tube. It will complywith the above stated conditions of velocity and straight trajectory.

It may be fitted with a target-seeking head, as shown at 21 in Fig. 9,for correcting its trajectory at the end of its travel, this head beingpreferably housed in an axial recess provided for this purpose in thearmored point 2. This head will operate supplementary control members(for instance spoilers) distributed regularly over the periphery of theprojectile body.

In a general manner, while I have, in the above description, disclosedwhat I deem to be practical and efficient embodiment of my invention, itshould be well understood that I do not wish to be limited thereto asthere might be changes made in the arrangement, disposition and form ofthe parts without departing from the principle of the present inventionas comprehended within the scope of the accompanying claims.

What I claim is:

1. A rocket propelled device of the class described, comprising: asmooth elongated hollow body of generally circular cross-section, saidbody defining a combustion chamber; directing means carried by saiddevice and maintaining said body in an upwardly inclined attitude duringflight thereof through the atmosphere for producing an aerodynamiclifting force acting on the surface of said body; a combustiblepropellant charge disposed in said combustion chamber, said charge beingformed to produce gaseous products of combustion at a varying rate, themanner of variation of said rate being predetermined by saidformation ofsaid charge; and nozzle means communicating with said chamber fordirecting said gaseous combustion products rearwardly to produce athrust for forward propulsion of said device, the magnitude of saidthrust being controlled by said formation of said charge to maintainsaid lifting force continuously at a value which decreases in accordancewith the loss of total weight of said device accompanying combustion ofsaid charge.

2. A device according to claim 1, in which lifting force is maintainedat a value substantially equal to said total weight.

3. A device according to claim 1, wherein said directing means maintainssaid upward inclination unchanged and in which the relationship betweensaid lifting force and said total weight of said device is determinedsolely by said formation of said charge.

4. A device according to claim 1, wherein said combustible charge hasits own center of gravity disposed rearwardly of the center of gravityof said entire device including said charge, whereby combustion of saidcharge will cause the center of gravity of said device to move forwardlyduring the courseffof said combustion and decrease the angle of saidinclination to decrease said lifting force in accordance with thedecrease in the total weight of said device.

5. A rocket propelled device of the class described, comprising a bodydefining a combustion chamber; nozzle means communicating with saidchamber for directing gases formed therein rearwardly to produce athrust for propelling said device forwardly; means for causing said bodyto assume an upwardly inclined angle for producing an aerodynamiclifting force during flight of said device through the atmosphere;apropellant charge disposed i said combustion chamber, said propellantcharge being shaped to expose a continuously decreasing area forcombustion, thereby producing gaseous products of combustion at acontinuously decreasing rate, said rate of combustion decreasing in astructurally predetermined manner in accordance with the loss of weightof said device caused by combustion of said charge, said charge being sopositioned with respect to the center of gravity of said device and theline of action of the force produced by said aerodynamic deflectingsurface, that the angle, of said inclination is controlled during thecourse, of said combustion directly and solely as a concurrent result ofsaid decreasing rate of combustion, together with the decrease in theweight of said device accompanying said combustion of said propellantcharge and any displacement of the center of gravity of said deviceaccompanying said combustion.

6. A device according to claim 5, wherein the angle of said inclinationis continuously controlled to maintain the lift produced by saidaerodynamic support substantially equal to the decreasing total weightof said device.

7. A self-propelled flying device which comprises, in combination, astreamlined body, a jet propulsion system for said body including a mainpropulsion engine and a launching propulsion engine located behind saidmain engine, a charge of fuel for each of said propulsion engines, themass of the full charge of fuel of the main propulsion engine having itscenter of gravity located rearwardly of the center of gravity of saidentire device, both of said engines being arranged to operate from thestarting of said flying device but the mass of fuel of said launchingengine being determined to last for only a fraction of the time ofoperation of said main engine, and aerodynamic means carried by saidbody for giving it a positive incidence position relatively to itstrajectory.

8. A self-propelled flying device which comprises, in combination, astreamlined body, a jet propulsion system for said body including a mainpropulsion engine and a launching propulsion engine located behind saidmain propulsion engine, said launching propulsion engine including arearwardly directed nozzle at the rear end of said body, a charge offuel for each of said propulsion engines, the mass of the full charge offuel of the main propulsion engine having its center of gravity locatedrearwardly of the center of gravity of said entire device, both of saidengines being arranged to operate from the starting of said flyingdevice but the mass of fuel of said launching engine being determined tolast for only a fraction of the time of operation of said main jetengine, aero dynamic means carried by said body for giving it a positiveincidence position relatively to its trajectory, deflector means movablysupported by said body inside said nozzle for controlling the meandirection of the jet issuing therefrom, and aerodynamic means carried bysaid body and responsive to angular displacements, away from apredetermined position, of the axis thereof with respect to thedirection of its trajectory for controlling said deflector means inresponse to said displacements to vary the direction of the jet to tendto restore said axis into said predetermined position with respect tosaid trajectory.

'9. A self-propelled flying device which comprises, in

combination, an aerodynamic streamlined body, vanes at the rear end ofsaid body in planes substantially radial to the longitudinal axisthereof, a jet propulsion system carried by said body, said body havingtwo jet passages opening rearwardly thereof, said jet propulsion meansincluding means to supply propelling fluid to a first of said passagesduring launching only and to a second of said passages during a longerperiod at least after launching, deflector means movable with respect tosaid first passage for varying the mean direction of the fluid issuingtherefrom during launching, and aerodynamic means carried by said bodyand responsive to angular displacements, away from a predeterminedposition, of the axis thereof with respect to the direction of itstrajectory for controliing

